You will want to take a drill bit, I used a 3/8 inch, and drill through the fiberglass in various spots along the top of the stringer. You are looking for water damaged wood and water trapped inside. Do this every 2 feet. You don't need to do deep to see if it is rotten.
If no damage is found...
Here is a good article...just scroll down to the engine part, https://www.sbmar.com/articles/installing-shafts-logs-struts-rudders-with-your-favorite-engine-transmission-part-2/
think poly is bad...try vinyl ester. That stuff smells like a school bus on fire.
I ended up on VE for my rebuild (87 Ski Centurion, gutted to the hull and complete update/rebuild) as it is stronger than PE and easier on the wallet than epoxy. Just layout and prep everything, wet your glass...
Yeah, the dreaded 22' off rooster tail. As the back of the boat goes deeper, the bump gets bigger. Just look at all the wake surfing boat wakes.
If the back rides shallower, it gets smaller.
It also moves closer and further from the boat depending on speed.
No need to spend money if you can...
Doubt the prop will get rid of the rooster tail. You might try redistributing weight and/or adding some weight to the nose area. This can help reduce your issue, at least it did in my case and it is the cheapest.
I would also look for some stainless steal plate, 3/8 inch thick and as wide as your engine stringers, bedded and leveled to mount your engine mounts onto. Helps distribute the weight of the engine.
